Polytype Stability and Defect Reduction in 4H-SiC Crystals Grown via Sublimation Technique

Abstract

ABSTRACTReproducible growth of 4H-SiC with good crystalline quality has been obtained in a temperature interval around 2350°C and on 4H-SiC C-face seeds. It has been observed that morphological instability may appear at the initial stage of growth, causing formation of defects. Experimental evidence has been found that supersaturation and surface kinetics are responsible for the polytype stability, while growth front and growth mode address defect reduction. An explanation of the findings has been suggested. It has been shown that starting the growth with a relatively low growth rate ( ≈ 100 μm/h ) can be beneficial for the crystal quality.